A review of solubility data for solid compounds in sub-and supercritical fluids published in the literature between 2005 and 2010 is given in tabular form along with the temperature and pressure ranges and the correlation methods applied by the authors for modeling the experimentally determined data. Compounds are classified into groups on the basis of their chemical nature (inorganic, organometallic, aromatic, nonaromatic organic, polymer), except for biological and pharmaceutical compounds, which are considered as a separate group based on their functionality. For each group of compounds, new findings are reviewed and discussed. Supercritical CO 2 was the preferred solvent for most of the applications, although an increasing interest in other solvents at elevated pressure has been observed, especially for fluorinated hydrocarbons, water, and propane.

Biodegradable polymers have been developed rapidly in the last years and are widely used today in the fields of pharmacy, clinical biomedicine, cosmetic, medical, packing industries, tissue engineering, agriculture and other areas. The interest in biodegradable polymers has been increasing, mainly due to rising oil prices, which is the basic feedstock of plastic derived from petroleum, and also due to the problem of the removal of waste plastics that accumulate in the environment. Biodegradable polymers have many advantages in contrast to synthetic polymers and can be decomposed in the environment to non-hazardous substances. Biodegradable polymers are classified into two classes based on their synthesis i.e., synthetic and natural polymers. They are derived either from petroleum resources or from biological resources. The following review presents an overview of the different biodegradable polymers and their properties, current scientific research, applications, global production of bioplastic and replacement of conventional plastic.

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PRODUCTION OF BIOGAS BY SCF TECHNOLOGY Article Highlights • An overview of the state-of-the-art of hydrogen production technologies • An overview of recently published papers dealing with SCWG of model compounds • Summary of investigations on SCWG of agricultural and food processing wastes in recent 3 years • Technical requirements and fundamental studies to support gasification for hydrogen production Abstract Hydrogen is expected to become an important fuel in the long-term since in combination with fuel cells it offers the opportunity of an intrinsically clean energy supply. By application of supercritical water gasification (SCWG) concept, sustainable hydrogen can be produced from biomass and waste. This paper offers an overview of some recently published research dealing with SCWG of model compounds and a summary of the investigations on SCWG of real agricultural and food processing wastes. In the frame of our work, intense research was performed to support analyses of SCWG of glycerol and was supported by the investigation of phase equilibrium for the systems gas/water and gas mixtures/water. When glycerol/water solutions were directly injected in the reactor operating at supercritical conditions, gases with high C2+ were obtained by the reforming in supercritical water unit. To reduce the hydrocarbon concentrations and to obtain a syngas with higher CO/CO 2 ratios from a mixture of gases (H 2 , CO, CO 2 and CH 4), catalytic reactions at high pressure and temperature were introduced reflecting in an increase of the content of H 2 and CO. Solubility measurements were conducted for the binary systems of gas and water at elevated pressures and temperatures.

The binary system of vitamin K3 and CO2 was investigated at temperatures of 40, 60 and 80 ?C up to a pressure of 40 MPa. Solubility was measured by a static-analytic method. Partial molar volumes were determined by a method involving a vibrating tube densimeter. The solubility of vitamin K3 in CO2 is found as a function of pressure and temperature. The highest solubility (31.16?10-4 mol?mol-1) was attained at a pressure of 25.40 MPa at temperature of 40?C. However, at temperature of 60?C and a pressure of 24.02 MPa, the solubility was 18.79?10-4 mol?mol-1. Solubility was lower at a temperature of 80?C and a pressure of 22.06 MPa (6.48?10-4 mol?mol-1). The partial molar volumes are negative and the dissolved vitamin K3 has a minor impact on the density of the solution of K3 in CO2 compared to the density of the pure CO2.